LATE-BREAKING ABSTRACT: Vocal cord dysfunction (VCD) in mild and severe asthma

Abstract

Vocal Cord Dysfunction in mild and severe asthma Introduction: Vocal cord dysfunction (VCD) causes vocal cord narrowing during inspiration resulting in airflow obstruction and may contribute to breathlessness in asthma. VCD is detected in more than 40% of severe disease but it is not known if the condition is limited to severe asthma and if dysfunctional breathing is associated. Method: Patients with mild to severe asthma (total n=155) were recruited from general practice and hospital asthma clinics and spirometry was conducted. VCD was diagnosed during inspiration using dynamic 320-slice computerised tomography (CT) of the larynx, a quantitative method capable of measuring real-time vocal cord dimensions during breathing. Excessive narrowing is recognised if a predetermined lower limit of normal is exceeded. Asthma control was evaluated using ACT and ACQ5 questionnaires and dysfunctional breathing was assessed via Nijmegen questionniare. VCD was compared in asthma severity. Results: In the overall group (n=155) VCD was detected during inspiration in 42 cases (27.1%). Patients with severe uncontrolled asthma (n=68) characterised by airflow limitation (FEV 1 Conclusion: VCD is frequently detected in asthma, more so in severe disease. Airflow limitation coupled with dysfunctional breathing has a strong association with VCD. Further studies are needed to determine if VCD worsens asthma symptoms and to ascertain which treatments can improve asthma severity.